Online Program

Safety profile of quadrivalent human papillomavirus vaccine: Canadian experiences

Monday, November 4, 2013 : 1:10 p.m. - 1:30 p.m.

Lawrence C. Loh, MD, MPH, Public Health Agency of Canada, Ottawa, ON, Canada
Jean Nkanza, MPH, Public Health Agency of Canada, Ottawa, ON, Canada
Julie Lafleche, BSc, Public Health Agency of Canada, Ottawa, ON, Canada
Barbara Law, MD, FRCPC, Public Health Agency of Canada, Ottawa, ON, Canada
Purpose: Health Canada approved the use of a quadrivalent vaccine against human papillomavirus (qHPV) in 2006, and by 2010 all Canadian jurisdictions had school-based immunization programs targeting girls. Opponents to these efforts have raised various concerns, particularly around the safety of the vaccine. This paper describes the safety profile of qHPV based on 6 years of reporting to the Canadian Adverse Event Following Immunization Surveillance System (CAEFISS). Data used: Reported adverse events following immunization (AEFIs) following qHPV administration from June 2006 to December 2011 and available in CAEFISS as of December 31, 2012.

Methods: Related CAEFISS AEFI reports were coded using standard terms from the Medical Dictionary for Regulatory Activities (MedDRA) and classified by reason for reporting, time to onset, and severity. Using SAS, descriptive analyses examined key trends and patterns.

Results: By December 2011, with over 3 million doses of qHPV distributed, 1389 AEFI reports involved qHPV. Most commonly reported AEFIs were rash, vaccine site pain and swelling, and non-anaphylactic allergic reactions. 51 AEFIs (3.7 %) met the criteria for serious (≥ 1 outcomes of: hospitalization, prolongation of existing hospitalization, permanent disability, or death). Of these the majority had alternate explanations for the reported event (29) or insufficient information to assess the role of vaccine (18). Events related to vaccination (4) were: post-syncopal head injury, anaphylaxis, myalgia and prolonged injection site pain.

Implications: Post-market experiences with qHPV in Canada are consistent with pre-market clinical trial observations, and match other national experiences and World Health Organization conclusions. Healthcare providers and public health authorities should promote its continued use.

Learning Areas:

Clinical medicine applied in public health
Protection of the public in relation to communicable diseases including prevention or control
Public health or related public policy
Public health or related research

Learning Objectives:
Explain the structure of vaccine safety mechanisms in Canada, using monitoring of quadrivalent HPV as an example Analyse trends of AEFIs related to quadrivalent HPV vaccination as described by a national reporting system for AEFIs, and determine the related safety profile Discuss ways to reassure the public of the safety and efficacy of quadrivalent HPV vaccination and strategies to improve coverage with quadrivalent HPV in the general public.

Keyword(s): Immunizations, Drug Safety

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I am a board-certified public health physician employed by the Public Health Agency of Canada who oversaw the formulation of the study, data collection and analysis, and final review and summary.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.